code: def _cubic(x):
      x = asarray(x, dtype=float)
      b = BSpline.basis_element([-2, -1, 0, 1, 2], extrapolate=False)
      out = b(x)
      out[(x < -2) | (x > 2)] = 0
      return out
  
file_path: scipy/scipy/signal/_bsplines.py
imports: from numpy import asarray, pi, zeros_like, array, arctan2, tan, ones, arange, floor, r_, atleast_1d, sqrt, exp, greater, cos, add, sin
  from ._spline import cspline2d, sepfir2d
  from ._signaltools import lfilter, sosfilt, lfiltic
  from scipy.interpolate import BSpline
label_desc: Use image node_id 3 for calling a global function with example usage: _cubic(x) and returns: out